Lethal Company multiplayer not working? Fix it here.

Can't join friends in Lethal Company

Lethal Company uses Steam invites; a Strict NAT blocks the host from being reachable. Use the lobby code as a fallback.

1. Check and fix your NAT type — Strict NAT is the #1 cause of 'can't join friends'. You need Moderate or Open to host and to receive invites reliably.
   • On Steam: Settings → In-Game → check the 'NAT' indicator, or test via Steam's network settings.
   • On Xbox: Settings → General → Network settings → 'NAT type'.
   • On PlayStation: Settings → Network → View Connection Status → 'NAT Type'.
   • If Strict: enable UPnP and/or port-forward (see those fixes). Tether to a phone hotspot once to confirm — if it works there, the issue is your home router.
2. Use the lobby / join code instead of a friend invite — Steam and platform friend-invites fail far more often than copy-paste codes. Most co-op games have a 'share lobby code' button.
   • Host creates the lobby, then copies the lobby/join code (not the friend invite).
   • Send the code in chat; the joiner pastes it into 'Join with code'.
   • If invites still fail, this bypasses the broken invite pipeline entirely.
3. Restart Steam / Epic / the console client — The overlay and friend-presence service occasionally desyncs, so invites never arrive. A client restart re-syncs it.
   • Fully quit Steam/Epic (system tray → Exit, don't just close the window).
   • Reopen and log back in.
   • On console, quit to dashboard and restart the app.
4. Host starts the game, opens the terminal or pause menu, and shares the lobby code if the Steam invite doesn't arrive.

Lethal Company multiplayer not working

1. Power-cycle your router and relaunch the game — A 30-second router reboot clears stale NAT and UPnP leases that silently break peer-to-peer connections. Fully quit the game (don't just minimise) and reopen it.
   • Unplug the router for 30 seconds, then plug it back in and wait for full sync.
   • Completely close the game (check Task Manager / Force Quit — overlays can leave it running).
   • Relaunch the game and try joining again.
2. Enable UPnP on your router — UPnP lets the game open its own port automatically. With it off, you'll often get Strict NAT and can't host or receive invites.
   • Log in to your router admin page (usually 192.168.0.1 or 192.168.1.1).
   • Find 'UPnP' or 'Universal Plug and Play' and turn it ON.
   • Save and reboot the router, then retry the game.
3. Turn off VPN, proxy, and 'kill switch' tools — VPNs and routing tools reroute P2P traffic and trigger Strict NAT or total blocks. Disable them for the session.
   • Fully quit your VPN app (not just disconnect — quit it).
   • Disable any proxy in Windows Settings → Network → Proxy.
   • Temporarily uninstall 'kill switch' / firewall-overlay tools if the issue persists.
   • Retry the join with a direct connection.

Lethal Company connection failed / black screen on join

1. Allow the game through firewall & antivirus — Over-aggressive security software flags game executables as threats and drops the connection after join.
   • Windows: Allow the game .exe through Windows Defender Firewall (Private + Public).
   • Add the game and Steam/Epic to your antivirus allow-list.
   • On Mac: System Settings → Privacy & Security → Firewall → allow the game.
2. Verify game files (fixes corrupted installs) — A half-downloaded or corrupted file causes 'connection failed' right after joining. Verifying redownloads the broken bits.
   • Steam: Library → right-click game → Properties → Installed Files → 'Verify integrity of game files'.
   • Epic: Library → three dots → 'Manage' → 'Verify'.
   • Console: a corrupted install usually needs a full reinstall from the store.
3. Use a wired connection to stop lag & drops — Wi-Fi jitter causes 'connection failed' and mid-session drops. A cable removes most of it.
   • Plug in Ethernet instead of Wi-Fi for the host especially.
   • If Wi-Fi only, move close to the router and use 5 GHz.
   • Close bandwidth-heavy apps (streaming, downloads) during play.

Lethal Company error codes explained

FAILED TO CONNECT

Host NAT is Strict. Host enables UPnP/port-forward or shares the lobby code.

BLACK SCREEN

Usually a verify-files + restart-client issue, not a network one.